JPH11312781A - Bridge type semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity by holding a semiconductor chip between two lead frames, to which units in bridge units are connected continuously in the X and Y directions and which have the same or approximately the same shape, and soldering the semiconductor chip. SOLUTION: A first lead frame, in which solder, etc., are printed beforehand onto die pad sections, is placed on a jig, etc., and diode chips D2, D3 and D1, D4 are incorporated into the die pad sections 1a, 2a while polarity is made to differ respectively. A second lead frame is put on so that the die pad sections 3a, 4a of the second lead frame having the same shape or approximately the same shape as the first lead frame are orthogonally crossed with the die pad sections 1a, 2a of the first lead frame. Since a bridge circuit is formed under the state, the bridge circuit is joined and unified by soldering by heating. Accordingly, a plurality of the bridge type semiconductor devices can be assembled simultaneously only by the semiconductor chip and solder and the two lead frames having approximately the same shape, and productivity is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a structure of a bridge type semiconductor device applied to electric and electronic equipment and the like, and a method of manufacturing the same. (2)

[0002]

2. Description of the Related Art As described in detail in Japanese Utility Model Registration No. 2566480, a method of manufacturing a conventional device of this kind is to attach each semiconductor chip to a die pad portion on a single lead frame (metal plate). (N-side or P-side) are aligned and mounted. Further, connectors are arranged and assembled between the chips, soldered, and then sealed with a resin by a transfer molding method or the like.

[0003]

In the above-mentioned conventional method, since the semiconductor chips can be incorporated with the same conductivity polarity, there is an advantage that the number of assembling steps can be greatly improved in this respect. There is a problem as a simultaneous mass production method because a step of connecting with a connector is required, and there is a problem that the shape of the product becomes large.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a stable production method and apparatus suitable for mass production that can be adapted to miniaturization, high reliability and low cost of electronic equipment in recent years. I do.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to an X direction and a Y direction.
A semiconductor chip is sandwiched between two lead frames of the same shape or substantially the same shape in which bridge unit units are connected in the direction, and soldering is performed. Further, by removing a part of the lead frame in a state where the semiconductor chip is assembled, a structure similar to that of a single chip is obtained, and productivity can be improved. By using a laser as a removing method, cutting can be performed without giving a mechanical stress to the semiconductor chip.

(3)

According to the first aspect of the present invention, there is provided a die pad portion which is arranged in parallel with each other and has a space for mounting two semiconductor chips at intervals, and a terminal portion integral with the die pad portion. A method of manufacturing a bridge type semiconductor device, wherein a semiconductor chip is sandwiched and soldered between die pads of a first lead frame and a second lead frame in which a plurality of metal plate units are connected in the X and Y directions. A method is provided, which enables mass production of bridge diodes.

The invention of claim 2 enables mass production of a resin-sealed bridge diode by adding a resin-sealing step. The invention according to claim 3 provides a method for manufacturing a bridge type semiconductor device including a step of removing a part of one of the lead frames by laser cutting prior to a resin sealing step. Smooth the flow to prevent resin leakage and improve product reliability.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a bridge type semiconductor device including a cutting step of dividing the first and second lead frames into bridge unit units after soldering the semiconductor chip. Prevents damage to the semiconductor chip at the time of division.

According to a fifth aspect of the present invention, there is provided a first and second die pads which are mounted with different conductive polarities on one of the die pads arranged in parallel.
Semiconductor chip, the third and fourth semiconductor chips, the other die pad portion disposed on the semiconductor chip in a direction substantially perpendicular to the die pad portion, and the first and second semiconductor chips extending from the one die pad portion. The lead terminal, the third and fourth lead terminals extending from the other die pad portion in the opposite direction to the lead terminal, the die pad portion, the semiconductor chip, and the resin portion for sealing a part of the lead terminal are referred to as ( 4) To provide a bridge-type semiconductor device provided.

[0010]

1, 2 and 3 are a plan view, a side view and an electrical equivalent circuit diagram of a bridge type semiconductor device showing an embodiment of the present invention, wherein D 1 to D 4 are semiconductors (diodes). Chips, 1 to 4 are lead terminals, and 16 is a resin part. The lead terminals 3 and 4 and the die pads 3a and 4a integrated with the lead terminals 3 and 4 are disposed in a substantially oblique direction in parallel with each other. Alternatively, it has a space for mounting D2 and D3, and is divided from one lead frame described later. The lead terminals 1 and 2 on the back side of the device also have similar die pad portions 1a and 2a, and are separated from the other lead frame. And each die pad 3a, 4a and 1
Semiconductor chips D1 to D4 are sandwiched between a and 2a so as to have different conductive polarities (P or N), and this structure is a so-called small and thin surface mount type (SMD). Incidentally, the structure of this embodiment has a shape of about 5 mm in length, about 4 mm in width, and about 1.5 mm in height.

4 and 5 show the structure of a lead frame applied to the present invention. FIG. 4 (a) is a plan view and FIG. 4 (b) is a partially enlarged view. In the drawing, A is one lead frame, B is the other lead frame, and in one lead frame A, 5 and 5a are side rails serving also as a frame, 6 and 6a.
Denotes a pilot hole, and AU has a die pad unit 1a, 1b which is an electrode plate unit in the frame and is arranged substantially parallel to the lead terminals 1 and 2. A plurality of the unit units are connected in the X direction (arrow) and the Y direction in the frame.

Next, the other lead frame B in FIG.
8a and a unit unit BU. Note that, in the unit BU, the die pad portions 3a and 4b are disposed in a substantially parallel state in a horizontal direction.

(5) Next, a method for manufacturing the device of the present invention will be described with reference to FIGS. 4, 5, 6 and 7. First, a lead frame A on which solder or the like is printed in advance on a die pad portion is placed on a jig or the like (not shown). Then, the diode chips D2 and D3
And D1 and D4 with different polarities. Next, the lead frame B is placed so that the die pad portions 3a and 4a of the lead frame B are orthogonal to the die pad portions 1a and 2a. In this state, a bridge circuit is formed, which is joined and integrated by soldering by heating. FIG. 6 shows this state. (a) is a plan view and (b) is a side view.
Incidentally, the lead frames A and B have, for example, a structure having 25 pieces in the X direction and five pieces in the Y direction for 125 pieces in order to assemble a plurality of semiconductor devices at the same time.

In the next step, the semiconductor device is formed with a resin portion 16 by transfer molding or the like for the purpose of securing reliability and mechanical strength. Before the rail is cut, the side rails are double (7, 5), which makes it difficult to fix the resin part when forming it by the transfer molding method.
There is a risk that resin will enter between the side rails,
Therefore, it is necessary to remove one of the side rails 7 after assembly. When cutting with a die using a press or the like, a mechanical stress is applied to the semiconductor chip to cause cracks in the solder at the connection portion.
Is removed. FIG. 7 shows this state, and FIG.
(b) is a side view.

Next, in the resin sealing step, the resin portions 16 are formed in the respective unit portions by a transfer molding method or the like, and unnecessary frames exposed by a cutting device or the like are removed and divided into individual bridge diodes.

FIGS. 8A and 8B are plan views showing another embodiment of the lead frame applied to the present invention. FIG. 8A shows a lead frame A, FIG. 8B shows a lead frame A, and FIG.
The figure shows a state where a semiconductor chip is sandwiched. In this embodiment, the frame A has the same shape as the previous embodiment (FIG. 4) (b).
In the figure, the frame B has the same shape as that of the frame A. In this structure, two identical frames (A, B) are combined, so that the frame itself is easy to make and productivity is improved. Note that the bridge diode after completion has a substantially rhombic planar shape, so that heat generated from the semiconductor chip can be evenly dispersed.

[0017]

As described above, the bridge type semiconductor device of the present invention has been described. However, the same effect can be obtained in a semiconductor device having a terminal portion other than four terminals. In addition, the longer the lead frame length of the present invention, the higher the productivity. The length of the lead frame is not limited to a fixed length, but has a wide range of application. Further, a bridge-type semiconductor device having high productivity can be provided because a plurality of semiconductor chips, solder for connection and two lead frames of substantially the same shape can be simultaneously assembled. Unnecessary portions can be easily removed without applying stress to the lead frame in a mechanically weak state before forming the resin portion by using a laser.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a side view showing one embodiment of the present invention.

[Figure 3] Electrical equivalent circuit diagram

FIG. 4 is a structural diagram of a lead frame A applied to the present invention.

FIG. 5 is a structural diagram of a lead frame B applied to the present invention.

FIG. 6 is a process chart (7) for explaining the production method of the present invention.

FIG. 7 is a process chart illustrating a production method of the present invention.

FIG. 8 shows another embodiment of the lead frame applied to the present invention.

[Explanation of symbols]

 1,2,3,4 Lead terminal 1a, 2a, 3a, 4a Die pad part 5,5a, 7,7a Side rail 6,6a, 8,8a Pilot hole AU, BU Unit unit D1, D2, D3, D4 Semiconductor ( Diode) chip 16 resin

Claims (5)

[Claims] 1. A plurality of metal plate units provided in parallel to each other and having a space for mounting two semiconductor chips with a space therebetween, and a metal plate unit having a terminal unit integrated therewith in the XY direction. A method for manufacturing a bridge-type semiconductor device, wherein a semiconductor chip is sandwiched and soldered between respective die pads of a connected first lead frame and a second lead frame. 2. The method for manufacturing a bridge-type semiconductor device according to claim 1, further comprising a step of sealing with a resin after soldering. 3. The method for manufacturing a bridge type semiconductor device according to claim 1, further comprising a step of removing a part of one of the lead frames prior to the resin sealing step. 4. The method according to claim 1, further comprising the step of dividing the first and second lead frames into bridge unit units after soldering the semiconductor chip. 5. A first semiconductor chip, a second semiconductor chip, and a third semiconductor chip mounted on one of the die pads arranged in parallel with different conductive polarities, and the die pad on the semiconductor chip. The other die pad portion, which is arranged in a direction substantially perpendicular to the portion, first and second lead terminals extending from the one die pad portion, and a third lead terminal extending from the other die pad portion in a direction opposite to the lead terminal. A bridge type semiconductor device comprising: a fourth lead terminal; a die pad portion; a semiconductor chip; and a resin portion for sealing a part of the lead terminal.